The interface superconductivity of Bi2Se3/Fe–Se heterostructure

Bi 2 Se 3 /Fe–Se heterostructures on Si(100) substrates have been prepared by radio frequency magnetron sputtering technique. The thickness of FeSe 2 film is an important factor for the properties of Bi 2 Se 3 /Fe–Se heterostructures. Our Bi 2 Se 3 /Fe–Se heterostructural samples showed ferromagnetism, which increase with increasing thickness of FeSe 2 layer. However, when the FeSe 2 layer is as thin as 20 nm, superconductivity could be observed through magnetization measurements, due to the existence of superconducting Fe–Se. Thus the Bi 2 Se 3 /Fe–Se heterostructure provides an approach to achieve both ferromagnetism and superconductivity simultaneously in interface, as well as to realize the interplay between a superconductor and a topological insulator.